<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>04_浮动测试</title>
  <style>
    .fu {
      background-color: #ff0;
      overflow: hidden;
      width: 400px;
      /*height: 50px;*/
    }
    .fu>div {
      width: 100px;
      height: 100px;
      border: 5px solid #000;
    }
    .z1 {
      background-color: red;
      float: left;
    }
    .z2 {
      background-color: green;
      float: right;
    }
    .z3 {
      background-color: beige;
      float: left;
    }
  </style>
</head>
<body>
<div class="fu">
  <div class="z1"></div>
  <div class="z2"></div>
  <div class="z3"></div>
</div>
</body>
</html>